Accompanying advancements in technologies, various distance measuring devices and methods have been invented. A simple method for measuring a distance from a reference point to an object may be to roll a wheel from the reference point to the object and calculate the number of rotating times of the wheel times the perimeter of the wheel.
Or, a measuring device may emit an infrared ray toward an object and receive the reflected infrared ray for evaluating the distance by recording the time lap between the emitting and the receiving of the infrared ray. Alternatively, the phase of a modulated light beam can be measured to provide the distance information. Such devices use a technology called “Time Of Flight”. They suffer from noise created by strong reflecting objects and many can't be used in natural daylight. Those measuring devices and methods are limited to be used in some particular environments. Other devices based on stereo matching can be used under natural light and outdoors but require intensive computations. There is a need for a new device and method for measuring distances both in and outdoors, and with less intensive computations.